In the finishing of concrete and stone floors, it customarily is the practice to grind and polish the surfaces of such floors to provide consistently smooth finishes. Such finishing typically is performed by machines consisting of a motor, a planetary disk mounted on an output shaft of the motor and a disk provided with a grit surface mounted on the planetary disk. In the use of such machines, however, because of the uneven surfaces of floors and the planar surfaces of grinding disks, it has been found that low spots of floor surfaces are not effectively ground and polished unless an excessive amount of concrete or stone is removed to make the floor even and planar. Such condition results in not only the removal excess material but the excessive use of grinding disks, energy and manpower.
In the prior art, there has been developed a type of machine intended to address the shortcoming of prior machines as described which utilizes a carrier disk mounted on the output shaft of the motor, a planetary disk provided with a plurality of grinding heads mounted thereon and a compression spring interposed between the carrier and planetary disks. Such machine, however, also has been found to be ineffective in achieving planar surfaces of uneven concrete or stone floors without excessive grinding and the use of excessive grinding disks, energy and manpower. Accordingly, it is the principal object of the present invention to provide a machine of the type described which is operable and effective in grinding and polishing an uneven concrete or stone surface to a consistently smooth floor without the excessive removal of material and the use of excessive amounts grinding disks, energy and manpower.